This invention relates to an apparatus for enrobing medicine and other ingestible tablets in a digestible film.
The pharmaceutical industry commonly provides drugs in the form of a capsule or tablet that can be readily swallowed by a person. The dosage form known as a tablet is solid and hard with a predetermined shape. Its active ingredients are held together with a suitable binder.
Recent U.S. Pat. No. 5,146,730 issued Sep. 15, 1992 to Banner Gelatin Products Corp. teaches a method and apparatus for producing medicine tablets that are enrobed in a gelatin coating formed by applying two layers of film to opposite sides of the tablet. Hard cores or preforms are dispensed on a self-timed basis into simultaneous contact with the two films which are supported on coacting rotary dies that come together to form a nip. The hard cores contact the films adjacent this nip at places which overlay recesses formed in the dies. The elastic films deform around each core and are sealed by the dies to each other. The dies then cut the covered cores from the films.
One of the difficulties of this known apparatus is that the rotary die members which are believed to be made of metal are quite expensive to manufacture. If one or both of the rotary dies should be damaged for any reason, it may be necessary to completely replace one or both of the rotary die members at a substantial cost. Furthermore, if this should occur and it becomes necessary to shut down a manufacturing operation until the one or more rotary dies are replaced, there is likely to be substantial additional expense and loss as a result of the shutdown in operations.
Recent U.S. Pat. No. 5,682,733 issued Nov. 4, 1997 to the present applicant describes another apparatus for enrobing tablets, which apparatus employs a main linked track of die blocks with each block having a number of recesses formed in its top surface. There is also a revolving cooperating die device which can be either another linked track or a cylindrical rotary die and this device also has a plurality of recesses, each of which is cooperable with a recess of similar size in the main linked track to provide an enclosed cavity capable of holding one of the tablets. A gelatin strip is delivered to the main linked track and moves along its upper path. A tablet dispenser drops tablets into depressions formed in this gelatin strip. A second gelatin strip is delivered to the apparatus and is laid over the first strip when the two strips reach a region of contact.
It is an object of the present invention to provide an apparatus for enrobing tablets in a layer of gelatin, which apparatus employs rotary die assemblies each with a series of die blocks and which apparatus can be repaired should it become damaged with reasonable speed and at less expense than the prior art rotary die members.
It is another object of the present invention to provide relatively inexpensive die blocks for use in an apparatus for enrobing ingestible tablets, these blocks being made of a hard plastics material and each having a number of similar recesses formed in the top.
It is a further object of the present invention to provide the aforementioned inexpensive die blocks for enrobing tablets, these blocks having one or more passageways for applying vacuum to the or each recess formed in the block. With these blocks vacuum can be used to pull the adjacent gelatin web into the recess, thereby forming a cup to receive the tablet.